White Stadium sits in one of the least-visited areas of Franklin Park, a onetime jewel tarnished by time and undone by neglect.

It’s the 10,000-seat facility that is home to many of the city’s high school football teams in the fall, which means that their players get by without many of the basic amenities their suburban counterparts take for granted. But it is little used the rest of the year — not by other sports teams, nor by the neighborhood that surrounds it. Its current condition was summed up Sunday by a rusted padlock surrounded by signs ordering the community to keep out.

John Fish, the owner of Suffolk Construction Co. and evangelist for Boston high school sports, has a plan to change that. He is kicking off a $45 million project to return White Stadium to its former glory. The project will be formally unveiled on Wednesday night at a meeting of the Franklin Park Coalition.

“That’s the problem right there,” Fish said, fingering the lock. “We could talk all day, but that’s the problem right there.”

The investment Fish is planning would be an unusual infusion of private resources into high school sports, and into a community often ignored by downtown power brokers. Among the neighborhoods that would welcome such a major youth facility in the city is Bowdoin-Geneva.

The idea is to completely rework the stadium, while adding other uses. Those would include an athletic track, indoor and outdoor basketball courts, and classrooms for after-school tutoring and other activities. The stadium could become a hub of year round neighborhood activity, and could be open to the community, which is mostly shut out of it now.

A study by the management consultants McKenzie and Co. found that use of White Stadium would increase dramatically with upgraded facilities. They said more than five times as many athletes will use it, from 840 to 4,500, with a similar increase in the hours it would be in use.

Its current condition was summed up by a rusted padlock.

The planned renovation is a natural outgrowth of Boston Scholar Athletes, the program Fish started three years ago to support high school athletes academically and athletically. Students in that program now boast a graduation rate of 84 percent, compared with 64 percent for Boston students as a whole, and its students have seen a 190-point increase in their average SAT scores.

“This is not really about athletics,” Fish said of BSA. “It’s an academic program disguised as an athletic program.”

White Stadium fell into disrepair gradually, though a major fire about 15 years ago helped to seal its decline.

It says something about the state of neglect that, until last week no one was even sure who owned the place. The School Department, which has managed it for decades, thought it held the title to it, but actually it does not; it is owned by the George Robert White Fund, a charity that supports city-controlled projects.

Fish hired former city councilor Michael J. McCormack to help unravel the maze of legal and political issues involved in taking control of the property. Because Fish and other donors are understandably reluctant to pour millions of dollars into the renovation with no control over how it is managed, the likely resolution is for his group to lease it long-term from the White Fund.

Fish is a deep believer in the power of athletics to reach kids and to transform lives. That comes in part from his own experience. Severely dyslexic as a child, he credits his time as a three-sport athlete with giving him the confidence to conquer his disability.

“I‘m not a professional athlete — it was a means to an end,” Fish said. “It showed me that I wasn’t stupid, I wasn’t dumb. It showed me that I could be successful someday.”

He adopted high school sports as a philanthropic cause a few years ago, after reading a Globe series about the lousy condition of the city's high school sports facilities. It has become a consuming passion. Famous for his 4 a.m. workouts and 6 a.m. meetings, Fish doesn’t really do halfway.

Fish said he will kick off the fund-raising campaign with $5 million out of his pocket, as he did when he began Boston Scholar Athletes. Mayor Thomas M. Menino has endorsed the plan and the city’s financial commitment to it. Fish said he believes the business community will be eager to invest in the project as well, that they simply haven’t been approached.

The stadium and community center is a small but important investment, Fish said, in Boston’s youth.

“It’s about our future,” he said. “We are the first generation to leave the world worse off than we found it. This is a little stop in doing something about that. White Stadium will stay the way it is for the next 20 years if we don’t so something about it.”